Collecting eight tracks that are untitled and, presumably, unmastered, the new project comes more or less a full year after Lamar released his masterpiece third album, To Pimp a Butterfly, which SPIN dubbed the Best Album of 2015. The new songs’ names all feature the word “untitled,” a number, and then a date — for example, “untitled 04 08.14.2014″ and “untitled 05 09.21.2014.” Producers on the LP are mostly unknown, although Swizz Beatz noted on Instagram that his 5-year-old son with Alicia Keys, Egypt, apparently produced “untitled 07 l 2014 – 2016.”

News of the surprise record leaked on Thursday night, when Spotify accidentally uploaded details about the album hours before it was officially available for streaming and purchase.